Scale loop



N. H. ANDERSON scams: LOOP Aug. 112, 1924.

Filed March 24, 1922 Patented Aug. l2, iaaa.

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NILS H. ANDERSON, OF TRUMBULL, CONNECTICUT, ASSIGNOR TO THE E. 84 T. FAIR- BANKS & COMPANY, OF ST. JOHNSBURY, VERMONT, A CORPORATION OF VERMONT.

SCALE LOOP.

Application. filed March 24, 1922.

To all whom it may concern:

Be it known that I, Nlns H. ANDERSON, a citizen of the United States, residing at Trumbull, in the county of Fairfield and State of Connecticut, have invented a new and useful Improvement in Scale Loops, of which the following'is a specification.

This invention relates to those loops which are employed for connecting rods or links in platform and similar scales with the pivots that extend from the scale beams. The pivots are usually of the knife-edge type and the loops ordinarily have angular openings that co-operate with the knife edges of the pivots to afford the desired bearings. It is the general practice to form these loops into U-shape out of steel by drop forging or pressing, with punched or drilled holes in the ends. The holes are then machined and after the loops are hardened the bearing surface of the holes are stoned into alignment as near as possible. The finishing operation which is commonly performed by hand requires great skill and results in more or less imperfect bearing of loops upon the pivots.

The object of the present invention is to produce loops for use in connection with knife-edge pivots in scales, which are in expensive to manufacture and which can be made in quantities of light material with a certainty that in every case the bearing on the pivot will be full length and thereby accurate and durable.

This object is attained by forming U- shaped loops from relatively thin sheet metal, such as comparatively soft steel, with openings in the ends into which angular metal plates, desirably of hard steel properly shaped to fit the openings and pivots are loosely-inserted in: such manner that the plates are permitted a rocking adjust ment so that they will lie in contact with the knife edges of the pivots practically the full length of the plates.

In the accompanying drawings Figure 1 shows a portion of a scale beam with a loop which embodies this invention mounted on a knife edge pivot that projects from the scale beam. Fig. 2 shows on a larger scale a side view of a loop constructed accord" ing to this invention. Fig. 3 shows an edge view of theloop. Fig. 4 shows a modified form of the loop. Fig. 5 shows another modification.

Serial No. 546,251.

The beam 1 may be of any common form and construction and the knife-edge pivot 2 may be fastened to the beam in any suitable manner. The loop 3 at the end of the link 4- rests upon the knife edge of the pivot in the usual way.

The body 5 of the loop is drop forged or otherwise bent or pressed to U-shape desirably from relatively soft sheet steel. In the ends of the body of the loop are openings 6 that are preferably made rounded on the inside and angular on the outside. In the angular sections of the openings, angular bearing plates 7 are inserted. These plates are hardened and. the inner surfaces are ground upon a wheel so as to secure a comparatively sharp corner at the apex of the angle that will prevent the loop from shifting on the pivot when in use. The angularity of the opening in the bearing plates may be varied according to desire. The edges of these plates near the middle are desirably notched as at 8. The plates are passed endwise into the openings and then turned around so as to occupy the sections of the openings to which they loosely conform.

In the arrangement shown in Fig. 2, springs 9 are snapped into the circular sections of the openings for the purpose of preventing the bearing plates from becoming dislodged in case the loop is suddenly relieved of weight so as to cause a rebound. These springs are shown as having ears 10 that clasp the body of the loop at the sides of the openings and as having extensions 11 that press against the bearing plates. These. extensions however may be omitted if desired, but they are particularly serviceable where the angle of the opening in the bearing plates is relatively sharp as shown in Fig. 2.

Instead of providing springs for retaining the bearing plates as above described, lugs 12 may be swedged from the metal of the loop body below the ends of the plates for retaining them as shown in Fig. t. On account of the low cost of manufacture this form is preferable as it eliminates the necessity for springs, but it is not as con venient when it is desired to remove the bearing plates. In the embodiment illus trated in Fig. 5 the openings in the loop body are made of such shape that shoulders 13 are formed for supporting the bearing platesand preventing them from becoming dislodged.

The angular plates provide long bearing and they may be inserted in loops of relatively thin metal. In all of the forms the bearing plates are loosely fitted in the openings in the ends of the loop bodies and as the loops encircle the plates about midway of the ends the plates are free to rock and so adjust themselves that they will lie in contact With the knife edges of the pivots the full length of the plates. This invention provides firm, accurate and durable bearings Which can be cheaply manufactured of light stock, and readily permits the removal and insertion of a bearing plate at any time when necessary, for the parts are interchangeable.

' The invention claimed is:

1. A scale loop comprising a U-shaped body formed of a. single piece of metal having perforations through its ends, angular plates loosely inserted in said perforations, and means sprung into said perforations for retaining said plates in the perforations.

2. A scale loop comprising a U+shaped body formed of a single piece of metal having perforations with angular outer walls, through its ends, sheet metal angular plate-s loosely conforming to the angular Walls of said perforations, and removable means located in said perforations and engaging the Walls thereof and obstructing the plates from dislodgement.

3. A scale loop comprising a U-shaped body formed of a single piece of metal having perforations through its ends, the outer walls of which perforations are angular, angular plates loosely inserted in said perforations and fitting the outer angular \valls thereof, and springs encircling the inner Walls of said perforations with their ends arranged to retain the plates in position.

4-. A scale loop comprising a U-shaped body having openings in its ends, angular plates loosely inserted in said openings, and springs arranged in said openings, said springs having ears clasping the body of the loop, and projections pressing against the ends of the plates.

NILS H. ANDERSON. 

